Why can’t my Dockercontainer have a rest Api? (AWS) [closed]

I have a general question. I have a microservice. This is there to send notifications to customers. As soon as I start a get request, the contact is saved in the database and the message is sent to a notification provider. When I start my microservice local it works very well. The data is saved, the message is sent and then a browser window is opened that tells me the status of the message.
I have now set up my microservice architecture at Amazon (AWS). If I start a get request now the microservice will be executed. The contact is saved in the database but the message is not sent.
I use springboot for the microservice MVN and have packed these services in docker containers. These Docker containers run on a jdk-alpine Linux operating system. The interface to the notification provider runs via a REST API.
Can someone tell me why this doesn’t work? It can’t be because I don’t have a browser in the Docker, can it?